Class CreateInstanceRequestBuilder (2.15.1)

void CreateInstance(google::cloud::spanner_admin::InstanceAdminClient client,
                    std::string const& project_id,
                    std::string const& instance_id,
                    std::string const& display_name,
                    std::string const& config_id) {
  namespace spanner = ::google::cloud::spanner;
  spanner::Instance in(project_id, instance_id);

  auto project = google::cloud::Project(project_id);
  std::string config_name =
      project.FullName() + "/instanceConfigs/" + config_id;
  auto instance =
      client
          .CreateInstance(spanner::CreateInstanceRequestBuilder(in, config_name)
                              .SetDisplayName(display_name)
                              .SetNodeCount(1)
                              .SetLabels({{"cloud_spanner_samples", "true"}})
                              .Build())
          .get();
  if (!instance) throw std::move(instance).status();
  std::cout << "Created instance [" << in << "]:\n" << instance->DebugString();
}